Personal and contextual determinants of COVID-19 vaccination intention: a vignette study

ABSTRACT

Background

This vignette study explores which factors contribute to higher COVID-19 vaccination intentions.

Methods

Between the 4^th-11 January 2021, we recruited 15,901 Belgian citizens (M_age = 50.11 years, range 18–100) through convenience sampling to participate in a vignette study. In each vignette, we manipulated contextual determinants consisting of different factors. Each participant rated six vignettes in terms of the outcomes ‘vaccination intention’ and ‘recommendation to others.’ Finally, we explored the benefits of tailored communication by examining whether these ratings depended upon citizens’ initial motives for vaccination.

Results

Participants are most likely to accept a vaccine when they expect no or only small side effects, when the vaccine offers a 95% protection, and when people can no longer infect others (p < 0.001). The possibility to receive the vaccine at home or at the GP’s office, highlighting that most citizens are willing to get vaccinated, and emphasizing the protective benefits for others yielded additional positive effects (p < 0.001). Results showed that tailored communication has a small but significant effect, especially for individuals high on distrust-based amotivation (p < 0.01).

Conclusion

In addition to vaccine characteristics, there is room for policymakers to respond to those determinants that fall under their control and can thus be highlighted within communication campaigns.

KEYWORDS:

• Motivation
• COVID-19
• vaccination attitudes
• preference study
• Self-Determination Theory

Acknowledgments

We would like to address special thanks to the Deputy Prime Minister and Minister of Social Affairs and Public Health, Frank Vandenbroucke, for his suggestion to conduct a vignette study.

Author contribution statement

All authors have (1) substantially contributed to the conception, study design, execution, acquisition of data, data analysis, and interpretation, and (2) drafted or written, or substantially revised or critically reviewed the article.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Data availability statement

All de-identified data, analysis code, and research materials are available at Zenodo. The study was not preregistered.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/14760584.2022.2105212

Notes

1. Unlike effect sizes that are traditionally used (e.g. Cohen’s d), a factor’s importance weight is relative to the importance weights of other factors included in the study, with the sum of all importance weights reaching 100%. Therefore, a factor’s importance weight provides a more intuitive measure of its relevance compared to more typical measures of effect sizes [65]. Although we can more easily compare the importance of one factor to another within a single study, the disadvantage of an importance weight relative to other effect sizes is that we cannot compare a factor’s importance weight between studies that combine different factors [66].

2. When including both types of amotivation separately in the model, distrust-based amotivation was negatively related to both vaccination behaviors (β_intention = −.20, β_{recommendation} = −.25, p < 0.001), whereas effort-based amotivation only showed a significant negative relation with vaccination recommendation (β_{recommendation} = −.04, p < 0.001), but not with vaccination intention (β_intention = −.01, p > 0.05).

Additional information

Funding

The Motivation Barometer is funded by the Special Research Fund of Ghent University [BOFCOV2020000701] and the federal Belgian Ministry of Social Affairs and Public Health.